I disassemble all of the assemblies and clean the metals parts
with Bleche White and/or a Scotch Brite pad. I always install
new coil sleeves and inspect stops, plungers, and arms for any
damage. All of these assemblies should move freely when you
re-assemble them. If they don’t you did something wrong
and need to work on it. Most of these metal parts just need
a good cleaning and don’t need to be replaced.

Some like to buy brand new assemblies instead of cleaning them.
I figure I save an average of three to four hundred dollars
a pin by cleaning instead of replacing. When I’m done
the assemblies function like new.